by Fredreka Schouten and Christopher Schnaars, USA TODAY

by Fredreka Schouten and Christopher Schnaars, USA TODAY

WASHINGTON - Paul Singer, the hedge fund billionaire whose demands helped drive Argentina to its second debt default in 13 years, has emerged as one of the biggest players on this nation's political stage before November's elections, a USA TODAY analysis of campaign records shows.

Singer, the billionaire founder of Elliott Management, has pumped more than $5 million into the bank accounts of super PACs, Republican congressional candidates and party committees since Jan. 1, 2013.

The giving has landed Singer membership in an exclusive club of midterm mega-donors. In all, four individuals hit the $5 million mark in this election cycle, the review found.

Singer's aides did not immediately respond to questions about his recent political activity.

The biggest spender by far is another billionaire hedge fund founder, Democrat Tom Steyer, who has invested more than $20.3 million to help elect candidates who agree with his positions on climate change.

The political parties are waging an expensive fight for control of the Senate, where Republicans need to net six seats in November to capture the majority and dictate the agenda on Capitol Hill during the last two years of President Obama's tenure.

Steyer says he is a counterbalance to Republican tax-exempt groups that are active in elections but don't disclose their spending or donors.

"Outside money is having a dispositive role in any kind of close campaign," said Chris Lehane, a top political adviser to Steyer. "It's really critical for Democrats to know that there's going to be a force out there ‚?¶ that's willing to stand up against the enormous amount of money coming from the other side."

The other members of the $5 million club:

‚?ĘFormer New York City mayor Michael Bloomberg has donated nearly $9.5 million to an array of organizations and candidates, including his gun control group and Senate Majority, a super PAC aiding Democrats' efforts to retain their hold on the chamber.

Bloomberg, an independent, also contributed a combined $500,000 to super PACs that helped two Republican incumbents, Sens. Thad Cochran of Mississippi and Lindsey Graham of South Carolina, withstand Tea Party challenges. Graham co-authored a bipartisan bill to overhaul the nation's immigration system -- a top issue for Bloomberg. The measure passed the Senate last year but has failed to move in the U.S. House.

"Mike Bloomberg strongly supports people who can put aside party differences and work with those across the aisle to actually accomplish changes -- from either party," spokesman Stu Loeser said in an email.

‚?ĘChicago media mogul Fred Eychaner donated more than $5.7 million, the majority of which went to the Senate Majority super PAC.

Steyer, who sold his stake in Farrallon Capital Management in late 2012 to focus on politics and the environment, has pledged to spend $50 million of his own money to shape Senate and gubernatorial elections and to seek an additional $50 million from other donors.

Steyer accounts for most of the donations to his NextGen Climate Action super PAC, filings show.

Lehane said the political team is having "productive conversations" with other potential donors. Steyer is willing to commit more than his original pledge of $50 million to achieve his objectives, Lehane said.

"We're going to have the money," he said.

Singer, known for his libertarian leanings, is the only mega-donor focused largely on helping Republicans - a reversal from the 2012 election when deep-pocketed Republican givers, such as Las Vegas casino magnate Sheldon Adelson, dominated political spending.

More than half of Singer's money flowed to two super PACs active in this year's Senate races: American Crossroads, tied to GOP strategist Karl Rove; and Ending Spending Action, founded by TD Ameritrade founder J. Joe Ricketts. Ending Spending describes its mission as curbing government spending and reducing the national debt.

It has spent nearly $1 million to oppose Democrat Michelle Nunn in Georgia, one of two GOP Senate seats that Democrats view as competitive.

Singer's biggest checks, however, have gone to American Unity, part of a gay-rights coalition that has urged the GOP-controlled U.S. House to pass legislation banning workplace discrimination based on sexual orientation.

Singer has been perhaps best known in recent years for his relentless pursuit of Argentina in the courts and on Capitol Hill, stemming from the South American country's 2001 debt default.

Elliott Management and American Task Force for Argentina, a coalition tied to Singer, have racked up a combined $920,000 in federal lobbying expenses during the first six months of this year, congressional records show.

NML Capital, a subsidiary of Singer's hedge fund, scored major victories at the Supreme Court last month when the justices ruled that NML and other holdout creditors who refused to take about 25 cents on the dollar for their bonds had the right to seek Argentina's assets around the world.

The high court also refused to take up Argentina's appeal of court rulings in New York that held the country must make payments on the defaulted bonds to the holdouts. The hedge fund is owed more than $1.5 billion.

On Wednesday, Argentina failed to make a scheduled interest payment on its bonds as talks between the hedge-fund holdouts and the nation fell apart.